mySQL query to insert the last incremented id from two tables into one

Question

I am trying to figure out how to get the last incremented id from two different tables and insert those values into a third table. I have a working query for when it was only one table, utilizing last_insert_id(), but i am stumped on how to get something like last_insert_id() but getting it from two different tables.

(I am unable to post images on here, so here is a link to the 3 tables: https://imgur.com/a/cbHlHAW)

In my schema I want it so a single user can post multiple items. The ids for user_id and item_id will most likely be different values from each other.

Here is my current attempt at trying to figure it out.

begin;

INSERT INTO post_items(name,description,category,city,state,zip,item_condition)
VALUES('test','test','test','test','test',12345,'test');

INSERT INTO users(city,state,zip)
VALUES('test','test',12345);

INSERT INTO links(date_posted,link,item_id,user_id)
VALUES(now(), 'google.com',post_items.last_insert_id(),users.last_insert_id());

Commit;

I have try researching on how to get it to work, but no luck.

Before I added the table users and added user_id to the links table I had a working query to insert into both tables just the way I wanted it to.

INSERT INTO post_items(name,description,category,city,state,zip,item_condition)
VALUES('test','test','test','test','test',12345,'test');

INSERT INTO links(date_posted,link,item_id)
VALUES(now(), link,last_insert_id());

I know how I would make a select statement but I can't get a working insert statement.